You can't have every book known to man in your personal library. Space and money will limit your choices. And if you move often, you will need to own even fewer books, as they are often the heaviest and most expensive things to move.
What books should you make certain to have on your bookshelves? Having resource books is so helpful. It allows you to take advantage of teachable moments when your child is the most inspired to learn. Search for books that your library is getting rid of. Unfortunately, libraries often purge their older books. Yes, there are new things learned all the time, and they want to stay up to date. But books about birds, human anatomy, trees, stars, flowers, animals, rocks, shells, etc. will be most inspirational when they have the beautiful old drawings that the older books do. Many of the older books are not available on Amazon. But if you are wanting to buy some, here are some of the books I would suggest:
I would also recommend that once your kids are of "school age" you invest in a microscope. There are so many things to look at with a microscope. Tap water, saliva, dragonfly wings, leaves, and pond water all reveal God's glory and design.
Wish you were here!